Networks transmit data between devices using constructs known as data packets. A data packet includes a header which contains routing and other identification information and a payload which includes substantive data. A data packet also contains a signature that identifies the packet to network devices. The signature may identify the type of the packet and its source and destination, for example.
Devices on a network locate and identify a packet's signature in order to process the packet. The signature may be located anywhere in the data packet. A process known as deep packet inspection is used to search through data in the packet in order to locate the signature.
Like reference numerals in different figures indicate like elements.